The following description of the background of the invention is provided to aid in understanding the invention, but is not admitted to describe or constitute prior art to the invention. Various methods are available for administering therapeutic agents to a patient. Such methods include parenteral, oral, ocular, nasal, topical, and transmucosal administration. Variations of these different types of administrations exist. For example, parenteral administration includes intravenous, subcutaneous, intraperitoneal, intramuscular, intraosseous, and intramedullary injection. The chosen mode of administration should take into account the nature of the therapeutic compound and the illness being treated.
Certain potential pharmaceuticals are hydrophobic and typically have very low aqueous solubility and hence low oral bioavailability. Different techniques concerned with solubilizing hydrophobic compounds include those described by Praveen et al., U.S. Pat. No. 5,314,685, and Fernandes et al., U.S. Pat. No. 4,992,271, both of which are hereby incorporated by reference herein in their entirety, including any figures, tables, and drawings.
One measure of the potential usefulness of an oral formulation of a new pharmaceutical agent is the bioavailability observed after oral administration of the formulation. Various factors can affect the oral bioavailability of the drug. These factors include aqueous solubility, drug absorption throughout the gastrointestinal track, drug stability in gastrointestinal tract, and first pass effect. Aqueous solubility is one of the most important factors. The oral bioavailability of an aqueous solution formulation of a drug is generally used as the standard or the idea bioavailability against which other oral formulations are measured. Formulations of drugs that increase the relative bioavailability of the drug as compared to an aqueous solution are desirable, especially with hydrophobic compounds.